I have a 1993 Trek 830 Antelope that Im trying to bring life back into. Im looking to add some Rock Shox suspension forks but do not know anything about measurements or what to look for to fit on this bike. I came back from a local bike shop and they just told me that none of the new ones will work. I had someone tell me that the Rock Shox Judy will work, but do not know what measurements and if I get a threaded or thread less. I have my funds ready to buy but need help in selection something that will work. Any help would be GREATLY appreciated. Thank you in advance for any responses.

I am pretty sure that no fork will work without significantly changing your bike's handling. The handling will change because, in order to fit suspension in a fork, you need to increase the length from the fork's axel to crown (AC). Basically, early mountain bikes were built without the concept of suspension, so the forks had shorter axle to crown. Almost mountain bikes today are built around a longer AC, so even if they have rigid forks, you can swap on a suspension fork of the correct amount of travel (80 or 100mm if a rigid fork is available; full-suspension bikes often get longer travel). If you stick a suspension fork on, it will mess with your steering response (do some googling on fork trail) and raise your handlebars and bottom bracket. In short, adding suspension to your bike will make it ride worse, rather than better.

Don't do it! I tried that with my early 90s rigid bike and created a nightmare. I destroyed the bike's climbing and handling qualities. I bought 3 stems trying to fix it. I eventually found "ok" climbing and handling again but it wasn't worth it. The elastomer Judy was a joke for "suspension"--wasn't worth the time or money. If you want some more cush up front, get a higher volume tire and run lower pressure. Depending on your weight, you can run lower than the 35 psi most tires say. I'm 175 and went down to 28-30 with no pinch flatting. Older bikes don't have the clearance for bigger tires like the newer ones but I was able to run and a 2.2 and we put a 2.3 on my wife's bike. I used to run 1.95 or 2.0s.

Thank you so much for the replies and input to both Fotooutdoors & Bikeme. I owe both of you a beer. Fotooutdoors, you really explained it well for me. And after reading your comments I will leave it with the original forks. I have always loved the bike and put many many miles on it, but the last 8 years it has been parked most of the times. If it's not upgrading it then I'm not for it. Everything thing on my bike except tires are original from the day I bought the bike. I did order a new seat since the old one is ripped and I'm looking to upgrade the seat post. Any suggestions on that?

Make mine a Ballast Point Big Eye IPA, lol. Get a caliper and measure the diameter of your post--there are many sizes. Also make sure the new one is the same or close to your original. Some bike frames can't take too long of a post but your Trek isn't built like that. I had to get a new post for that old HT as the channels that hold the saddle rails wore and made the saddle tilt thus hurting my back. I personally wouldn't spend the money on a post unless you have the same prob as I did or the saddle clamp bolt stripped or something like that. Once you have the dia. and length, look at Kalloy (readily available and low $) or Easton or Truvativ (for something nicer but more $$).